1 Field of the Invention
The present invention relates to an ink jet recording apparatus wherein a reaction solution and an ink composition are deposited onto a recording medium to conduct printing and also relates to a tank containing the reaction solution for use in the ink jet recording apparatus.
2 Background Art
An ink jet recording method is a printing method wherein droplets of an ink composition are ejected and deposited onto a recording medium such as paper. This method has a feature that an image having a high resolution and a high quality can be printed at a high speed with a relatively inexpensive apparatus. In general, the ink composition used in the ink jet recording comprises water as a main component and, added thereto, a colorant and a wetting agent, such as glycerin, for prevention of clogging and other purposes.
A new ink jet recording method has been recently proposed which comprises applying a polyvalent metal salt solution onto a recording medium and then applying an ink composition containing a dye having at least one carboxyl group (for example, Japanese Patent Laid-Open No. 202328/1993).
Further, several other ink jet recording methods have also been proposed wherein two liquids, i.e., a polyvalent metal salt solution and an ink composition, are printed (for example, Japanese Patent Laid-Open Nos. 63185/1989, 240557/1991, 240558/1991, 52868/1996, and 207424/1997).
The claimed advantage of the ink jet recording methods using the two liquids is that, upon printing of the polyvalent metal solution (hereinafter often referred to as "reaction solution") and the ink composition onto a recording medium, the polyvalent metal salt combines mainly with a colorant to form an insoluble complex which can yield an image having water resistance and a high quality free from color bleeding.
The salt of a polyvalent metal, however, has low solubility in water. Therefore, use of a polyvalent metal salt solution after storage for a long period of time results in such an unfavorable phenomenon that a precipitate clogs a filter, inhibiting the reaction solution from being fed into a recording head, or otherwise the precipitate enters the recording head to unfavorably clog a fine nozzle.